1. General Information

Oxygen Sensor/Lambda Sensor, a critical component of automotive fuel injection system, measures and maintains the oxygen content in the exhaust gas to ensure optimal engine operation. To do this, an Oxygen Sensor/Lambda Sensor constantly monitors the air/fuel ratio of the exhaust gas at 14.7:1, the industry’s standard for lowest emissions. Too much oxygen in this ratio means the engine is running lean and that its performance is not optimal. Too little oxygen in this ratio means the engine is running rich and that it’s wasting fuel and creates excess emission.  Both conditions may shorten the lifespan of a vehicle’s engine and catalytic converter.

2. Oxygen Sensor Function

- Improve engine response & performance.
- Lower emissions.
- Improved gas mileage and fuel economy.
- Environmental friendly.
- Save money.

3. Oxygen Sensor Placement   

4. Aged and Failing Oxygen Sensors

Due to the harsh environment of vehicle’s engine and exhaust system, an Oxygen Sensor/Lambda Sensor will age gradually. “Aged” sensors will work less efficient and respond slower than “New” sensors, therefore, may cause premature failure of the catalytic converter. “Failing” sensors may cause by instant or gradual contact of silicon and lead compounds in the fuel. Both aged and failing sensors will cause problems such as poor fuel economy, failed emission tests, premature failure of catalytic converter, and poor performance of engine.

“Aged” sensors are inevitable whether through normal use or silicon and lead poisoning. Most OE manufacturers recommend checking and replacing Oxygen Sensor/ Lambda Sensor at every 40,000 to 60,000 miles.

5. Symptom of Poisoned or Damaged Oxygen Sensors  

- Lead Poisoning
Lead composite in the fuel may damage casing body as well as ceramic element inside. Immediate action to replace sensor and use only lead free fuels.

-Excessive Carbon / Soot Deposits
Soot produced by incomplete combustion of oil may cause blockage of frontal protection tube which lead to unstable and incorrect response time. Immediate action to replace sensor.

-Silicone Poisoning
Silicone contaminates the ceramic element in oxygen sensor which result in sensor functional failure. Immediate action to replace sensor and to use oxygen safe product.

6. Visual Inspection

Due to the sensitive and fragile nature of the ceramic element inside of an oxygen sensor, visual inspection of sensor may be useful to determine the cause of an failed oxygen sensor. The body casing should be checked for dents, which are caused by mechanical shock from transit or dropping of sensors during installation. Mechanical shock to the sensor body may cause damages  to the ceramic element inside that lead to non functional sensor. 

Lead wire and connector of the sensor should also be checked for cuts. Any damages will interfere with sensors signal.

7. Oxygen Sensor Diagonstics 

There are 3 methods to test an Oxygen Sensor/Lambda Sensor. The most traditional method is an on car test.  Install the sensor into the car and drive to see if its fuel economy improved and engine performance improved. The second method of sensor testing is by using an oscilloscope. An oscilloscope will check for output and response time of the sensor. The last method of sensor testing is by using a multi-meter. A multi-meter will check for function of the sensor in terms of output or no output.  It will also check for ohm resistance of the sensor heater. For diagnostic details, please contact Cabsen for technical support at info@cabsen.com.

8. Oxygen Sensor Compatibility

Due to the variance of application specifications; what may seem like a non-functional Oxygen Sensor/Lambda Sensor may not necessarily mean a defective sensor, but an incompatible sensor. Application variations may include differences in heater resistance, and element structure.  Differences in heater resistance may cause vehicle ECU to not recognize sensor output, which in turns cause the “check engine light” to turn on. The differences in element structure may mean the differences between Zirconium materials based or Titanium material based sensor. These two elements are not to be interchanged.

9. Recommended Handling

RECOMMENDED HANDLING
- Do not drop Oxygen Sensor/Lambda Sensor. Dropping of sensor may cause damage to the ceramic body of the sensor.
- Do not use impact wrench or conventional socket type wrench to install sensor.
- Though protected by silicon sleeves, do not allow wires to touch exhaust manifold and other hot component.
- Do not expose oxygen sensor to water, oil, windshield cleaner, anticorrosion oil, grease, terminal cleaner, etc.
- Do not use leaded fuels, silicone or metal addictive.
- Do not use over-the-counter fuel additives, which are not “Oxygen Sensor/Lambda Sensor safe”.
- Due to property of Oxygen Sensor/Lambda Sensor, zirconia based sensor should not be interchanged with titania based sensor under any circumstances
 
RECOMMENDED STORAGE
Oxygen Sensor/Lambda Sensor should be stored at temperature between -40℃ to +100℃. The relative humidity should be between 0% to 60%.